Aircraft control



July 11, 1944. J GRAY 2,353,303

AIRCRAFT CONTROL Filed Dec. 12, 1940 1 171427750). James 17.11 9P0).

Patented July 11, 1944 2,353,303

UNITED STATES EATENT OFFICE AIRCRAFT CONTROL James D. M. Gray, Toronto, Ontario, Canada. as-

signor of twenty per cent to Thomas J. Agar, and twenty-five per cent to Harry W. Terry and Herbert W. McIntosh, all of Toronto, Ontario, Canada Application December 12, 1940, Serial No. 369,707

3 Claims. (Cl. 244-410) The principal objects of this invention are to ward edge on the main wing structure or fuselage enhance the maneuverability of aircraft and to to pivot about a substantially common transverse provide an improved braking system which will axis indicated at 3, which axi is preferably aroperate efficiently in conjunction with the landranged forwardly of the rearward or trailing edge ing wheel brakes and the conventional control of the wing structure, so that when the flaps are means therefor in order to supplement their inactive they will be accommodated closely adbraking efiort selectively or collectively. J'acent to the undersurface of the wings to mini- The principal feature of the invention resides mize air resistance. in the novel combination with the selective brak- In aircraft construction of the low or undering means of the port and starboard wheels, of .10 slung wing type the air flaps l and 2 may extend air-brake flaps or the like which are so co-related well in under the fuselage so that their inner to the respective wheel brakes and control mechedges substantially meet adjacent the vertical anism thereof that application of both brakes central plane of the latter, particularly in singlesimultaneously will bring the respective flaps int-o engined craft, but in multi-engined craft they air-braking position while application of either 15 may be spaced apart a greater distance or may, the port or starboard wheel-brake will bring into in the higher wing type of craft, be located enplay only the port or starboard air flap. tirely at the outward side of the fuselage.

In the drawing, The landing wheels 4 and 5 are provided with Figure 1 is a front elevational view of an airany suitabl conventional form of braking equipcraft equipped with the present invention. an men-t (not shown) from which, in the present Figure 2 is a perspective view of the craft shown instance, hydraulic actuating cables or conduits in Figure l. 8 and I are shown extending.

Figure 3 is a diagrammatic view representative Brake control pedals 18 and 9 of any convenofahydraulic control system. tional form are represented in the p esent in- Figure 4 is a diagrammatic representation of a 2:3 stance as connected respectively with hydraulic mechanical control system. displacement pistons l8 and H arranged in fluid- It is common practice in the construction of displacement cylinders IZand l3. aircraft having landing wheels, to provide such A pair of hydraulic cylinders M and I5 are wheels with brakes which are adapted to be seassociated respectively with the flaps I and 2 and lectively or collectively operated by pressing down '30 are provided with pistons Hi and I! operatively on separate brake pedals or the like which are connected withthe respe'ctiveflaps.

respectively connected to the port and starboard The hydraulic conduits 6 and l, which are wheel brakes, either by mechanical connections preferably of the flexible form, are connected or hydraulically, or otherwise. with the displacement cylinders I2 and I3 re- It is the primary purpose of the present inven- 3 spectively, and branch tubular connections I8 tion to co-relate this selective type of braking and i9 lead from the conduits 6 and l and are system on aircraft with air flaps or other equivaconnected respectively with the flap control cylinlent air braking means so that the braking efders l4 and I5. fort of either wheel will be automatically supple- It will thus be seen that when the p brake mented by the air-braking means located on the Pedal 3 is depressed o brake the P Wheel the respective side of the aircraft, and by means of respective po ap I will be simultaneously 0D- hich simultaneous application of both wheel erated so that it will assume its braking position brakes will concurrently render both port d and thereby supplement the braking action of the starboard air brakes effective irrespective of port wheel- Similarly n the starboard brake whether the landing wheels have contacted the Pedal 9 is depressed the starboard flap 2 Will be ground. automatically swung downwardly into braking The present invention further contemplates im- DOSitiOII. t e eby supplementing the braking proved maneuverability of the plane, not only in tion of the Starboard Wheelturning on the ground but also during flight, When both brake pedals 8 and 9 are depressed wherein the heel-brake c t l mechanism 5 to brake both port and starboard wheels both of comes a control factor in the operation of the airthe a r flaps Will be brought downwardly into craft in flight. braking position.

In carrying th present inve ti i t effect While for purposes of illustration I have shown according to the preferred form, a pair of air a imp i more or less di ramma i rr n flaps l and 2 are pivotally mounted at their for- 55 ment of a hydraulic control system, it will be readily appreciated that other forms of controls may be resorted to including servo mechanisms which may be hydraulic, electric, vacuumatic or mechanical or any suitable combination of these.

In the modification shown in Figure 4 the wheels 4 and 5' are provided with mechanical brakes (not shown) having operating cables 6' and 7 leading therefrom and connected with the brake levers or pedals 8 and 9' respectively. The air flaps l and 2 have connected therewith operating cables l8 and 19 which are also respectively connected with the brake levers or pedals 8' and 9' so that on operation of either of the mechanical brakes the respective air flaps will be moved into efiective braking position.

It will be readily appreciated that a particularly eflicient combination is provided for in the invention herein defined involving many advantages over the conventional independently controlled one-piece air flap.

When a pilot is about to land the aircraft and it is desired to decelerate the air speed as much as possible before making contact with the ground or runway, both brake pedals will be simultaneously depressed so that both flaps will be brought down into effective braking position so that when the wheels finally contact the runway the combined braking action of the air flaps and wheels will become effective to quickly check the speed of the craft.

When the aircraft is about to take off and im-- mediately after the wheels have left the ground the pilot, by pressing down both brake pedals,

'may bring the port and starboard flaps down in angular relation to the line of flight, thereby giving greater lift to the craft.

The selectively controllable flaps provide for better maneuverability either on the ground or in the air and enable better cross-wind landings and take-ofis. Further, more effective control of the craft is provided for particularly near the stalling speed, since increased lift can be quickly thrown to either the port or starboard wing, and the relative control of the flaps will be an important factor in turning at slow speed and with the minimum banking.

The selectively operable air flaps will also serve an important function in co-operation with the wheel brakes during turning operations on "the ground, since, when the port or starboard brake is applied, the respective flap only will be lowered and will receive the thrust of the slip stream, thus greatly assisting retarding action on the braked side of the craft.

It will be further appreciated that by enabling one flap to be lowered independently of the other the elfective control surface of the tail wing or rudder will not be blanketed which is an objection to the present one-piece type of flap, and when applied to dive-bombing craft improved control in the yawing plane will be provided for.

The improved control herein defined when applied to multi-motored aircraft provides an improved controlling factor on the failure of one or more wing engines, thereby relieving the strain on the rudder and controls and reducing pilot fatigue.

While for purposes of illustration I have shown simple exemplary forms of the present invention and control means therefor, I may resort to various modifications or structural interpretations within the essential spirit of the invention.

What I claim as my invention is:

1. In an aircraft having landing wheels at the port and starboard sides, individually manually actuated brake-control means for said port wheel and individually manually operable brake control means for said starboard Wheel, a pair of air-brake flaps transversely pivoted 0n the aircraft substantially parallel with the wing structure one at each side of the vertical centre plane, and operable to swing downwardly in an angular relation to the wings, an operating connection between the port flap and the first-mentioned wheel brake-control means to swing the port flap downwardly into air-braking position on the actuation of said port wheel braking means, and an operative connection between the starboard flap and the second-mentioned brakecontrol means to swing said starboard flap downwardly into air-braking position on the actuation of said starboard wheel braking means.

2. In an aircraft having landing wheels each provided with separately and selectively operable braking means, a pair of air flaps pivotally mounted transversely of and below the wings of said aircraft, foot control means for individually swinging said air flaps, and means connecting said foot control means individually with said individual braking means.

3. In an aircraft having landing wheels disposed at the port and starboard sides of the craft and separate brake control means for selectively braking said port and starboard wheels, air flaps pivotally mounted in horizontal alignment transversely beneath the main wing structure for exerting a selective airbraking effort at one or the other or at both sides of the longitudinal centre simultaneously of said aircraft, and separate pedals operatively connected each with the air flap and brake of one side only of the aircraft.

JAMES D. M. GRAY. 

